From patchwork Sun Jun 18 19:18:54 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 9794951 X-Patchwork-Delegate: johannes@sipsolutions.net Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 013276032B for ; Sun, 18 Jun 2017 19:19:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D77FB28174 for ; Sun, 18 Jun 2017 19:19:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CA299283B4; Sun, 18 Jun 2017 19:19:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 47EEC28174 for ; Sun, 18 Jun 2017 19:19:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752253AbdFRTTK (ORCPT ); Sun, 18 Jun 2017 15:19:10 -0400 Received: from frisell.zx2c4.com ([192.95.5.64]:55573 "EHLO frisell.zx2c4.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751014AbdFRTTJ (ORCPT ); Sun, 18 Jun 2017 15:19:09 -0400 Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 0a93ae5d; Sun, 18 Jun 2017 19:17:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=zx2c4.com; h=from:to:cc :subject:date:message-id:in-reply-to:references; s=mail; bh=Q6nl oVMeclP3V3Nse3D1k154XKc=; b=dpXXYeetzUJPUdzmwMh25beAgHF8FQVwhDpX VYZwVth5AyiVgDvO0tj8QIKt0+4hSWIt1V+1M2jApZvw1hnedY0SmVQwgw8Oujn0 BeQOyhbM1siJ6GcQFayqUajc5+iT0ORrjUeaUGWuCi1XNf1QaX+IaTLVB/Zd8LVa GRguotWbVoQEnv5FzNZfTL38hqRiW5niqyY7KiWq2JMpYuZpyi1MbIMlagcIlWOO OOE8RLdTQN70rsVmFstqFJ7xVNJ4zv/52f+hE+Qh1HAS+q+/Dx7dMyX/4B2bavKZ XGhOzYYbcU61G7zoVzyUwE7GEdYZ6L7oguWH9zf3Mkr5xYu4dA== Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 069082f7 (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256:NO); Sun, 18 Jun 2017 19:17:17 +0000 (UTC) From: "Jason A. Donenfeld" To: gregkh@linuxfoundation.org Cc: "Jason A. Donenfeld" , Johannes Berg , linux-wireless@vger.kernel.org, stable@vger.kernel.org, Johannes Berg Subject: [PATCH] mac80211/wpa: use constant time memory comparison for MACs Date: Sun, 18 Jun 2017 21:18:54 +0200 Message-Id: <20170618191854.17767-1-Jason@zx2c4.com> In-Reply-To: <1497720871224217@kroah.com> References: <1497720871224217@kroah.com> Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Otherwise, we enable all sorts of forgeries via timing attack. Signed-off-by: Jason A. Donenfeld Cc: Johannes Berg Cc: linux-wireless@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Johannes Berg --- Here's the backport for 3.18. net/mac80211/wpa.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c index 983527a4c1ab..49592c7e4199 100644 --- a/net/mac80211/wpa.c +++ b/net/mac80211/wpa.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "ieee80211_i.h" #include "michael.h" @@ -150,7 +151,7 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; michael_mic(key, hdr, data, data_len, mic); - if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) + if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN) != 0) goto mic_fail; /* remove Michael MIC from payload */ @@ -520,7 +521,7 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx) queue = rx->security_idx; - if (memcmp(pn, key->u.ccmp.rx_pn[queue], IEEE80211_CCMP_PN_LEN) <= 0) { + if (crypto_memneq(pn, key->u.ccmp.rx_pn[queue], IEEE80211_CCMP_PN_LEN) <= 0) { key->u.ccmp.replays++; return RX_DROP_UNUSABLE; } @@ -771,7 +772,7 @@ ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) bip_aad(skb, aad); ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, skb->data + 24, skb->len - 24, mic); - if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { + if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic)) != 0) { key->u.aes_cmac.icverrors++; return RX_DROP_UNUSABLE; }